Evaluation of human health potential impacts for Lebanese pollutant emission scenarios

Abstract

Life Cycle Assessment (LCA) is a method for evaluating the environmental impacts of a product, service or process during it whole lifecycle, in other words from the extraction of raw materials to the disposal. This project is only limited to the third phase of LCA which deals with the evaluation of the environmental impacts of different products (LCIA), processes or services. This project stresses on the "human toxicity" impact category. The potential environmental impacts caused by a pollutant can be determined using the intake fraction "iF" concept. The iF is defined as "the measurement of pollution that can be used in the determination of the environmental health impact of a pollutant source. It is the ratio of the mass of a pollutant inhaled or ingested to the mass of the pollutant emitted." The iF can be predicted using multimedia and multi-pathways fate and exposure models. Pollution in Lebanon is a major concern. Although there are already some studies on the fate of chemicals in air or water, there are no studies available that on the combined multimedia partitioning of a pollutant in environmental compartments and the exposure of humans to releases. Therefore, the main objective of the project is to create a multimedia and multipathways fate and exposure model to predict the intake fraction resulting from a Lebanese pollutant emission. In order to achieve this objective, the undertaken steps were: 1. Select an appropriate model framework for a fate and exposure model; 2. Determine fate and exposure parameters for Lebanon; 3. Create a Lebanese fate and exposure model; 4. Determine the intake fractions for air and water releases of organic pollutants. More specifically, - The IMPACT 2002 model was chosen for the calculation of iFs; - A set of 32 organic chemicals was chosen to represent the variability of physicochemical properties of organic chemicals; Fate and exposure parameters (geographical, meteorological, demographic and hydrological data) were determined; - The intake fractions were calculated for air and water emissions and were then compared with results related to Canadian emission scenarios; - Finally, the created model was run again against 11 persistent organic pollutants (POPs) specific for Lebanon. Results showed that, for the set of 32 organic pollutants, the highest iF was attributed to Carbon tetrachloride for inhalation and Hexabromo-Benzene for oral for air emissions and for water emissions. Results also indicated that for the Lebanese releases of POPs, the highest iF was attributed to DDE and DDT for air emissions and to DDE and Toxaphene for water emissions. When compared to Canadian releases, some iFs resulting from Lebanese emissions were higher. This shows the importance on developing and implementing remediation strategies for priority pollutants.